To be honest, the best way is to use plug-in Wi-Fi controlled switches. These have an ESP8266 family of processor built-in and you can re-program them to run Blynk code (although they do have their own app that allows you to control them without the use of Blynk).
For my UK sockets I use the Sonoff S20 devices…
https://rover.ebay.com/rover/0/0/0?mpre=https%3A%2F%2Fwww.ebay.co.uk%2Fulk%2Fitm%2F153406031994
They are actually a bit bulky in my opinion, and for our holiday home in Spain I prefer some of the smaller devices, like these:
Pete.